This question was locked in an older post, however there was no resolution to the problem. I had a similar issue and was able to resolve it in the following manner with the help of the Account Security Adviser Team at Apple. Try these steps, and if they don't work, try calling apple. This may only work if you update your apple id to your new email address before losing access to the old address. In my case, I still had access to my old email address, but using the password recovery options provided did not work. Here's the sequence of what happened to me:
1) I opened itunes after not having used the music files I had stored for a long time. 2) Itunes said "this computer is not authorized to play " and specified I needed to authorize it using my old ID and pw. 3) Attempts to use all old and current passwords failed. I clicked on "Forget?" 4) This took me to the account recovery web page where there were two options:
a) Email recovery - Tried this several times and never got an email sent to my old email address. That is because Apple discarded this email when I updated my apple ID, right? Email Recovery Fails b) Security Questions - prompted me to enter my birthday. Here, I have read that a lot of folks have trouble because you get an error that says you have entered incorrect information. Pretty sure we all know our own birthdays right? The problem is Apple doesn't and you may not have told them recently or when you changed your id. So this option fails.
Meanwhile the files are sitting on your computer, you have paid dearly for them and now Apple is the bad guy for not letting you get access to them right? Maybe there is some DRM hack we can all google, right? Wrong, you just need to do the following.
1) Go to appleid.apple.com and click on Manage your Apple ID. 2) Login with your current/new apple id and verify that everything looks good here 3) Click on pw and security. In my case, I found I had not set any questions or birthday info here. If you have done this before, it should say "Please answer your security questions" 4) If you have not done this, or even if you think you have, and it is prompting you to create new ones, go ahead and make new ones, your old ones are gone. 5) Enter your birthday, guessing you can all handle that one:) 6) Scroll down and click save.
Now head over to the iTunes software. I had recently updated mine so it was the newer 11.01 interface where the menus and side bar are all hidden by default.
1) In the upper left there is a drop down, click show menu bar 2) now click on the View menu and click Show side bar (in case you were missing it, the ol' sidebar is back!) 3) In the sidebar, click iTunes Store. 4) You should see your current Apple Id in the upper left corner of the store. Click on it and click sign out. 5) Sign in with your current id 6) Now click on Store in the menu bar and click authorize this computer 7) Alternatively you can try and deauthorize and then reauthorize. Supposedly there is a way to deauthorize all machines, not seeing it at the moment, probably buried in preferences somewhere. This will ensure any old device you have discarded or sold are no longer able to claim access to your content.
This should get you going, hope you are as successful as I was. Play around with steps 4-7, not sure I got the order exact here as I was going from memory, but it should work. All my files seem to play now, unless of course someone else owns them:)